U.S. Pat. Nos. 4,839,104; 5,019,655; 5,196,607 and 5,466,880 as well as WO95/15299 describe various methods and processes for preparing 4-(3,4-dichlorophenyl)-3,4-dihydro-2H-naphthalen-1-one. None of these prior art patents describe or suggest the new instant process for the preparation of this valuable intermediate for the preparation of the antidepressant sertraline which is cis-(1S)(4S)-N-methyl-4-(3,4-dichlorophenyl)-1,2,3,4-tetrahydro-1-naphthal eneamine.
The instant process has the advantage of using a readily accessible and relatively inexpensive intermediate 1-naphthyl acetate which has high solubility in o-chlorobenzene.